The Experts below are selected from a list of 1929 Experts worldwide ranked by ideXlab platform
Baik S - One of the best experts on this subject based on the ideXlab platform.
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Significant suppression of leakage current in (Ba,Sr)TiO3 thin films by Ni or Mn doping
'AIP Publishing', 2018Co-Authors: Kh Ahn, Baik S, Ss KimAbstract:Effects of Ni or Mn doping in (Ba0.5Sr0.5)TiO3 thin films on leakage current behaviors of Pt/(Ba0.5Sr0.5)TiO3/Pt capacitors were investigated. The leakage current level was found to reduce significantly after the doping over a wide range of voltages and temperatures. The leakage current in an undoped capacitor was largely governed by the Fowler-Nordheim Tunneling, and its onset voltage was greatly increased in doped capacitors. The suppression of leakage current in doped capacitors appeared to be caused by a widened depletion layer, which decreases the likelihood of Tunneling. (C) 2002 American Institute of Physics.open116070sciescopu
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Microstructural effects on leakage current behavior of (Ba,Sr)TiO3 thin films for DRAM applications
TAYLOR & FRANCIS LTD, 2018Co-Authors: Kh Ahn, Kim S, Baik SAbstract:We have investigated the effects of microstructure on the leakage cur-rent behavior of Pt/(Ba,Sr)TiO3/Pt film capacitors. To single out the microstructural effects only, (Ba,Sr)TiO3 films of three different microstructures (granular, columnar, possibly epitaxial), but having an identical interfacial state density, were prepared using a seed layer by sputtering. The leakage behavior depends strongly on the film microstructure. Schottky emission dominates in the film composed of granular grains, while the epi-like film shows the higher leakage current and Fowler-Nordheim Tunneling mechanism. Interestingly, the film of columnar grains shows Tunneling at low temperatures and Schottky emission at high temperatures. We propose a model based on energy band diagrams explaining the results.X11sciescopu
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Change of conduction mechanism by microstructural variation in Pt/(Ba,Sr)TiO3/Pt film capacitors
'AIP Publishing', 2018Co-Authors: Kh Ahn, Ss Kim, Baik SAbstract:The effects of microstructure on the leakage current behaviors in Pt/(Ba,Sr)TiO3/Pt thin film capacitors prepared by a radio-frequency magnetron sputtering technique were studied. Both applying an epitaxial seed layer and controlling post-annealing processes enabled us to obtain (Ba,Sr)TiO3 films of three different microstructures (granular, columnar, and epitaxial) but possessing an identical interface state with the Pt electrode. The Schottky emission dominates in the film composed of granular grains. In contrast, the Fowler-Nordheim Tunneling governs in the epitaxial film with much elevated leakage current levels. In the case of the columnar film, at low temperatures the Tunneling dominates, while at high temperatures the Schottky emission governs with intermediate leakage levels. An energy band model accounting for the change of leakage current mechanisms by microstructure variation is presented. (C) 2002 American Institute of Physics.open113231sciescopu
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Thickness dependence of leakage current behavior in epitaxial (Ba,Sr)TiO3 film capacitors
'AIP Publishing', 2018Co-Authors: Kh Ahn, Ss Kim, Baik SAbstract:Thickness dependence of leakage current behavior in Pt/(Ba,Sr)TiO3/Pt film capacitors was investigated by fabricating epitaxial (Ba,Sr)TiO3 thin films having different thicknesses of 55-225 nm but with an identical interface state on Pt(001)/MgO(001) substrates by a radio-frequency magnetron sputtering technique. In the 55-nm-thick film, the Schottky emission is found to be a main leakage mechanism over a wide electric field range. In sharp contrast, instead of the Schottky emission, the Fowler-Nordheim Tunneling dominates particularly in the thicker films (greater than or equal to90 nm) at high electric fields. According to the energy band model proposed to explain these results, the major leakage conduction mechanism is likely to be associated with overlapping of the depletion layers formed at the top and bottom interfaces. (C) 2003 American Institute of Physics. [DOI: 10.1063/1.1535750].open112626sciescopu
Di Bartolomeo Antonio - One of the best experts on this subject based on the ideXlab platform.
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Leakage and field emission in side-gate graphene field effect transistors
2016Co-Authors: Giubileo Filippo, Iemmo Laura, Luongo Giuseppe, Russo Saverio, Unal Selim, Di Bartolomeo AntonioAbstract:We fabricate planar graphene field-effect transistors with self-aligned side-gate, using a single lithographic step. We demonstrate side-gating below 1V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim Tunneling in vacuum, which becomes dominant at higher voltages. We report a field-emission current density as high as 1µA/µm between graphene flakes. These findings are important for the miniaturization of atomically thin devices
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Side-gate leakage and field emission in all-graphene field effect transistors on SiO2/Si substrate
'AIP Publishing', 2016Co-Authors: Di Bartolomeo Antonio, Giubileo Filippo, Iemmo Laura, Russo Saverio, Unal Selim, Romeo Francesco, Passacantando Maurizio, Grossi Valentina, Cucolo, Anna MariaAbstract:We fabricate planar all-graphene field-effect transistors with self-aligned side-gates at 100 nm from the main graphene conductive channel, using a single lithographic step. We demonstrate side-gating below 1V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim Tunneling in vacuum, which becomes dominant at high voltages. We report a field-emission current density as high as 1uA/um between graphene flakes. These findings are essential for the miniaturization of atomically thin devices.Comment: Research article, 8 pages, 5 figure
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Side-gate leakage and field emission in all-graphene field effect transistors on SiO2/Si substrate
arXiv.org, 2016Co-Authors: Di Bartolomeo Antonio, Giubileo Filippo, Iemmo Laura, Russo Saverio, Unal Selim, Romeo Francesco, Passacantando Maurizio, Grossi Valentina, Cucolo, Anna MariaAbstract:We fabricate planar all-graphene field-effect transistors with self-aligned side-gates at 100 nm from the main graphene conductive channel, using a single lithographic step. We demonstrate side-gating below 1V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim Tunneling in vacuum, which becomes dominant at high voltages. We report a field-emission current density as high as 1uA/um between graphene flakes. These findings are essential for the miniaturization of atomically thin devices
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Leakage and field emission in side-gate graphene field effect transistors
'AIP Publishing', 2016Co-Authors: Di Bartolomeo Antonio, Giubileo Filippo, Iemmo Laura, Romeo Francesco, Passacantando Maurizio, Russo S., Unal S., Cucolo, Anna MariaAbstract:We fabricate planar graphene field-effect transistors with self-aligned side-gate at 100 nm from the 500 nm wide graphene conductive channel, using a single lithographic step. We demonstrate side-gating below 1 V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim Tunneling in vacuum, which becomes dominant at higher voltages. We report a field-emission current density as high as 1 μA/μm between graphene flakes. These findings are important for the miniaturization of atomically thin devices
Cucolo, Anna Maria - One of the best experts on this subject based on the ideXlab platform.
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Side-gate leakage and field emission in all-graphene field effect transistors on SiO2/Si substrate
'AIP Publishing', 2016Co-Authors: Di Bartolomeo Antonio, Giubileo Filippo, Iemmo Laura, Russo Saverio, Unal Selim, Romeo Francesco, Passacantando Maurizio, Grossi Valentina, Cucolo, Anna MariaAbstract:We fabricate planar all-graphene field-effect transistors with self-aligned side-gates at 100 nm from the main graphene conductive channel, using a single lithographic step. We demonstrate side-gating below 1V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim Tunneling in vacuum, which becomes dominant at high voltages. We report a field-emission current density as high as 1uA/um between graphene flakes. These findings are essential for the miniaturization of atomically thin devices.Comment: Research article, 8 pages, 5 figure
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Side-gate leakage and field emission in all-graphene field effect transistors on SiO2/Si substrate
arXiv.org, 2016Co-Authors: Di Bartolomeo Antonio, Giubileo Filippo, Iemmo Laura, Russo Saverio, Unal Selim, Romeo Francesco, Passacantando Maurizio, Grossi Valentina, Cucolo, Anna MariaAbstract:We fabricate planar all-graphene field-effect transistors with self-aligned side-gates at 100 nm from the main graphene conductive channel, using a single lithographic step. We demonstrate side-gating below 1V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim Tunneling in vacuum, which becomes dominant at high voltages. We report a field-emission current density as high as 1uA/um between graphene flakes. These findings are essential for the miniaturization of atomically thin devices
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Leakage and field emission in side-gate graphene field effect transistors
'AIP Publishing', 2016Co-Authors: Di Bartolomeo Antonio, Giubileo Filippo, Iemmo Laura, Romeo Francesco, Passacantando Maurizio, Russo S., Unal S., Cucolo, Anna MariaAbstract:We fabricate planar graphene field-effect transistors with self-aligned side-gate at 100 nm from the 500 nm wide graphene conductive channel, using a single lithographic step. We demonstrate side-gating below 1 V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim Tunneling in vacuum, which becomes dominant at higher voltages. We report a field-emission current density as high as 1 μA/μm between graphene flakes. These findings are important for the miniaturization of atomically thin devices
John F Conley - One of the best experts on this subject based on the ideXlab platform.
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Demonstration of Fowler–Nordheim Tunneling in Simple Solution-Processed Thin Films
2018Co-Authors: Cory K. Perkins, John F Conley, Melanie A. Jenkins, Tsung-han Chiang, Ryan H. Mansergh, Vasily Gouliouk, Nizan Kenane, John F. Wager, Douglas A. KeszlerAbstract:The production of high-quality thin-film insulators is essential to develop advanced technologies based on electron Tunneling. Current insulator deposition methods, however, suffer from a variety of limitations, including constrained substrate sizes, limited materials options, and complexity of patterning. Here, we report the deposition of large-area Al2O3 films by a solution process and its integration in metal–insulator–metal devices that exhibit I–V signatures of Fowler–Nordheim electron Tunneling. A unique, high-purity precursor based on an aqueous solution of the nanocluster flat-Al13 transforms to thin Al2O3 insulators free of the electron traps and emission states that commonly inhibit Tunneling in other films. Tunneling is further confirmed by the temperature independence of device current
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investigation of the impact of insulator material on the performance of dissimilar electrode metal insulator metal diodes
Journal of Applied Physics, 2014Co-Authors: Nasir Alimardani, Sean W King, Benjamin French, Benjamin P Lampert, John F ConleyAbstract:The performance of thin film metal-insulator-metal (MIM) diodes is investigated for a variety of large and small electron affinity insulators using ultrasmooth amorphous metal as the bottom electrode. Nb2O5, Ta2O5, ZrO2, HfO2, Al2O3, and SiO2 amorphous insulators are deposited via atomic layer deposition (ALD). Reflection electron energy loss spectroscopy (REELS) is utilized to measure the band-gap energy (EG) and energy position of intrinsic sub-gap defect states for each insulator. EG of as-deposited ALD insulators are found to be Nb2O5 = 3.8 eV, Ta2O5 = 4.4 eV, ZrO2 = 5.4 eV, HfO2 = 5.6 eV, Al2O3 = 6.4 eV, and SiO2 = 8.8 eV with uncertainty of ±0.2 eV. Current vs. voltage asymmetry, non-linearity, turn-on voltage, and dominant conduction mechanisms are compared. Al2O3 and SiO2 are found to operate based on Fowler-Nordheim Tunneling. Al2O3 shows the highest asymmetry. ZrO2, Nb2O5, and Ta2O5 based diodes are found to be dominated by Frenkel-Poole emission at large biases and exhibit lower asymmetry. The ...
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impact of electrode roughness on metal insulator metal tunnel diodes with atomic layer deposited al2o3 tunnel barriers
Journal of Vacuum Science and Technology, 2012Co-Authors: Nasir Alimardani, John F Conley, William E Cowell, J F Wager, David R Evans, Matthew L Chin, Stephen Kilpatrick, Madan DubeyAbstract:Metal-insulator-metal (MIM) tunnel diodes on a variety of high and low work function metals with various levels of root-mean-square roughness are fabricated using high quality atomic layer deposited Al2O3 as the insulating tunnel barrier. It is found that electrode surface roughness can dominate the current versus voltage characteristics of MIM diodes, even overwhelming the impact of metal work function. Devices with smoother bottom electrodes are found to produce current versus voltage behavior with higher asymmetry and better agreement with Fowler-Nordheim Tunneling theory, as well as a greater percentage of functioning devices.
Nandita Dasgupta - One of the best experts on this subject based on the ideXlab platform.
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effect of barrier layer thickness on gate leakage current in algan gan hemts
IEEE Transactions on Electron Devices, 2015Co-Authors: Sreenidhi Turuvekere, Amitava Dasgupta, Nandita DasguptaAbstract:Gate leakage current mechanisms in Al0.28Ga0.72N/GaN high-electron mobility transistors with different barrier thicknesses are studied using temperature-dependent current–voltage characteristics. Poole–Frenkel emission and Fowler–Nordheim Tunneling are observed in the reverse bias. Beyond the threshold voltage, increase in gate leakage current with the increase in barrier thickness is observed. Furthermore, the gate leakage current has negative temperature dependence over a wide range of temperatures especially for the devices with a thicker barrier. This has been qualitatively explained with the help of secondary electron–hole pair generation in the channel.
